This second edition cancels and replaces the first edition (ISO 4230:1977). Is a supplement to ISO 2568 and ISO 4231 and lys down the dimensions of these screwing dies intended for production of taper pipe threads in accordance with ISO 7-1. With the exception of the die 1/16, the diameter, thickness and fixing dimensions are in accordance with ISO 2568 so as to permit the driving of hand-operated dies with the aid of the die stocks defined in that document.